ALDH2 and liver cancer: The ALDH2 Glu504Lys allele not only causes individuals to experience adverse reactions such as blushing after alcohol consumption, but it also increases the risk of heart disease (Shen et al. 1863), esophageal cancer (Suo et al. 2019), gastric cancer (Hidaka et al. 2015), liver cancer (Sakamoto et al. 2006), and other diseases in alcohol drinkers.